Withings Pulse
Credit: Photograph by Plamen Petkov

The Withings Pulse, a 1.5-inch rectangular pod (shown here in its wrist strap), logs loads of data: steps, stairs climbed, sleep patterns, time active, and calories burned. Killer feature: Press your finger to it and it displays your heart rate. It was the most accurate here, and it synced easily with its well-designed partner app. We loved its OLED touchscreen and long battery life, too. One nitpick: You can sync only via its app. [$100; withings.com]